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Publication numberUS6596126 B1
Publication typeGrant
Application numberUS 09/488,430
Publication dateJul 22, 2003
Filing dateJan 20, 2000
Priority dateJan 25, 1999
Fee statusPaid
Also published asCA2296892A1, CA2296892C
Publication number09488430, 488430, US 6596126 B1, US 6596126B1, US-B1-6596126, US6596126 B1, US6596126B1
InventorsThomas Gerard Shannon, Daniel Arthur Clarahan, Mike Thomas Goulet, Wen Zyo Schroeder
Original AssigneeKimberly-Clark Worldwide, Inc.
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Modified polysaccharides containing aliphatic hydrocarbon moieties
US 6596126 B1
Abstract
Modified polysaccharides (such as starches, gums, chitosans, celluloses, alginates, sugars, etc.), which are commonly used in the paper industry as strengthening agents, surface sizes, coating binders, emulsifiers and adhesives, can be combined into a single molecule with modified aliphatic hydrocarbons, which are commonly utilized, in conjunction with cationic moieties, as softeners, debonders, lubricants and sizing agents. The resulting molecule is a modified polysaccharide having an aliphatic moiety which can provide several potential benefits, depending on the specific combination employed, including: (a) strength aids that do not impart stiffness; (b) softeners that do not reduce strength; (c) wet strength with improved wet/dry strength ratio; (d) debonders with reduced linting and sloughing; (e) strength aids with controlled absorbency; and (f) surface sizing agents with improved tactile properties.
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Claims(5)
We claim:
1. A soft tissue sheet comprising a modified polysaccharide containing one or more aliphatic hydrocarbon moieties, said modified polysaccharide having the following structure:
Polysac—Z3R1
where
Polysac=is starch dextrin natural gum, carboxymethyl cellulose or chitocan;
R1=an organofunctional group containing a moiety consisting of a C8 or higher aliphatic hydrocarbon; and
Z3=—OCNH—.
2. A method of making a soft tissue sheet comprising the steps of: (a) forming an aqueous suspension of papermaking fibers; (b) depositing the aqueous suspension of papermaking fibers onto a forming fabric to form a web; and (c) dewatering and drying the web to form a soft tissue sheet, wherein a modified polysaccharide is added to the aqueous suspension or to the web during or after drying, said modified polysaccharide having the following structure:
Polysac—Z3R1
where
Polysac−is starch, dextrin, natural gum, carboxymethyl cellulose or chitosen;
R1=an organofunctional group containing a moiety consisting of a C8 or higher aliphatic hydrocarbon; and
Z3=—OCNH—.
3. The method of claim 2 wherein the modified polysaccharide is added to the aqueous suspension of fibers.
4. The method of claim 2 wherein the modified polysaccharide is added to the web during drying.
5. The method of claim 2 wherein the modified polysaccharide is added to the dried web.
Description

This application claims priority from U.S. Provisional Application No. 60/117,087 filed on Jan. 25, 1999.

BACKGROUND OF THE INVENTION

In the manufacture of paper products, such as facial tissue, bath tissue, paper towels, dinner napkins and the like, a wide variety of product properties are imparted to the final product through the use of chemical additives. Examples of such additives include softeners, debonders, wet strength agents, dry strength agents, sizing agents, opacifiers and the like. In many instances, more than one chemical additive is added to the product at some point in the manufacturing process. Unfortunately, there are instances where certain chemical additives may not be compatible with each other or may be detrimental to the efficiency of the papermaking process, such as can be the case with the effect of wet end chemicals on the downstream efficiency of creping adhesives. Another limitation, which is associated with wet end chemical addition, is the limited availability of adequate bonding sites on the papermaking fibers to which the chemicals can attach themselves. Under such circumstances, more than one chemical functionality compete for the limited available bonding sites, oftentimes resulting in the insufficient retention of one or both chemicals on the fibers.

Therefore, there is a need for a means of applying more than one chemical functionality to a paper web which mitigates the limitations created by limited number of bonding sites.

SUMMARY OF THE INVENTION

In certain instances, two or more chemical functionalities can be combined into a single molecule, such that the combined molecule imparts at least two distinct product properties to the final paper product that heretofore have been imparted through the use of two or more different molecules. More specifically, modified polysaccharides (such as starches, gums, chitosans, celluloses, alginates, sugars, etc.), which are commonly used in the paper industry as strengthening agents, surface sizes, coating binders, emulsifiers and adhesives, can be combined into a single molecule with modified aliphatic hydrocarbons, which are commonly utilized, in conjunction with cationic moieties, as softeners, debonders, lubricants and sizing agents. The resulting molecule is a modified polysaccharide having an aliphatic moiety which can provide several potential benefits, depending on the specific combination employed, including: (a) strength aids that do not impart stiffness; (b) softeners that do not reduce strength; (c) wet strength with improved wet/dry strength ratio; (d) debonders with reduced linting and sloughing; (e) strength aids with controlled absorbency; and (f) surface sizing agents with improved tactile properties.

Hence in one aspect, the invention resides in a modified polysaccharide containing one or more aliphatic hydrocarbon moieties, said modified polysaccharide having the following structure:

Polysac—Z3R1

or

—Polysac—Z3R1—Polysac—

where

Polysac=any polysaccharide, monosaccharide, or sugar residue, modified or unmodified.

R1=any organofunctional group with the only limitation being that R1 must contain a moiety consisting of a saturated or unsaturated, substituted or unsubstituted, linear or branched C8 or higher aliphatic hydrocarbon.

Z3=a bridging radical whose purpose is to attach the R1 functional moiety to the Polysac residue. Suitable bridging radicals would include but are not limited to —OOC—, —COO—, —NHCO—, —OCNH—, —O—, —S—, CONHCO, —NCOO, —OSO2O—, —OCOO—, —OOC—Ar—O—.

In another aspect, the invention resides in a paper sheet, such as a tissue sheet, comprising a modified polysaccharide containing one or more aliphatic hydrocarbon moieties, said modified polysaccharide having the following structure:

Polysac—Z3R1

or

—Polysac—Z3R1—Polysac—

where

Polysac=any polysaccharide, monosaccharide, or sugar residue, modified or unmodified.

R1=any organofunctional group with the only limitation being that R1 must contain a moiety consisting of a saturated or unsaturated, substituted or unsubstituted, linear or branched C8 or higher aliphatic hydrocarbon.

Z3=a bridging radical whose purpose is to attach the R1 functional moiety to the Polysac residue. Suitable bridging radicals would include but are not limited to —OOC—, —COO—, —NHCO—, —OCNH—, —O—, —S—, CONHCO, —NCOO—, —OSO2O—, —OCOO—, —OOC—Ar—O—.

In another aspect, the invention resides in a method of making a paper sheet, such as a tissue sheet, comprising the steps of: (a) forming an aqueous suspension of papermaking fibers; (b) depositing the aqueous suspension of papermaking fibers onto a forming fabric to form a web; and (c) dewatering and drying the web to form a paper sheet, wherein a modified polysaccharide is added to the aqueous suspension or to the web during or after drying, said modified polysaccharide having the following structure:

Polysac—Z3R1

or

—Polysac—Z3R1—Polysac—

where

Polysac=any polysaccharide, monosaccharide, or sugar residue, modified or unmodified.

R1=any organofunctional group with the only limitation being that R1 must contain a moiety consisting of a saturated or unsaturated, substituted or unsubstituted, linear or branched C8 or higher aliphatic hydrocarbon.

Z3=a bridging radical whose purpose is to attach the R1 functional moiety to the Polysac residue. Suitable bridging radicals would include but are not limited to —OOC—, —COO—, —NHCO—, —OCNH—, —O—, —S—, CONHCO, —NCOO, —OSO2O—, —OCOO—, —OOC—Ar—O—.

The amount of the modified polysaccharide added to the fibers can be from about 0.02 to about 2 weight percent, on a dry fiber basis, more specifically from about 0.05 to about 1 weight percent and still more specifically from about 0.1 to about 0.75 weight percent. The modified polysaccharide can be added to the fibers at any point in the process where the fibers are suspended in water.

As used herein, “polysaccharides” are carbohydrates that can be hydrolyzed to many monosaccharides and include, but are not limited to, starches (primarily starches from potato, corn, waxy maize, tapioca and wheat) which can be unmodified, acid modified, enzyme modified, cationic, anionic or amphoteric; carboxymethylcellulose, modified or unmodified; natural gums, modified or unmodified (such as from locust bean and guar); sugars, modified or unmodified; chitosan, modified or unmodified; and dextrins, modified and unmodified.

A “monosaccharide” is a carbohydrate that cannot be hydrolyzed into simpler compounds.

“Carbohydrates” are polyhydroxy aldehydes, polyhydroxy ketones or compounds that can be hydrolyzed to them.

As used herein, “aliphatic hydrocarbons” encompasses a broad group of organic compounds, including in general alkanes, alkenes, alkynes and cyclic aliphatic classifications. The aliphatic hydrocarbons can be linear or branched, saturated or unsaturated, substituted or non-substituted.

Methods of making paper products which can benefit from the various aspects of this invention are well known to those skilled in the papermaking art. Exemplary patents include U.S. Pat. No. 5,785,813 issued Jul. 28, 1998 to Smith et al. entitled “Method of Treating a Papermaking Furnish For Making Soft Tissue”; U.S. Pat. No. 5,772,845 issued Jun. 30, 1998 to Farrington, Jr. et al. entitled “Soft Tissue”; U.S. Pat. No. 5,746,887 issued May 5, 1998 to Wendt et al. entitled “Method of Making Soft Tissue Products”; and U.S. Pat. No. 5,591,306 issued Jan. 7, 1997 to Kaun entitled “Method For Making Soft Tissue Using Cationic Silicones”, all of which are hereby incorporated by reference.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a macroscopic structure of amphiphilic moieties attached in pendant fashion to a polysaccharide.

FIG. 2 shows a macroscopic structure of amphiphilic moieties attached in series to a polysaccharide molecules.

DETAILED DESCRIPTION OF THE INVENTION

To further describe the invention, examples of the synthesis of some of the various chemical species are given below.

Polysaccharides

Starches

Unmodified starch has the structure as shown below. Unmodified starches can differ in properties such as amylopectin : amylose ratio, granule dimension, gelatinization temperature, and molecular weight. Unmodified starches have very little affinity for fibers, and modifications are widely done to extend the number of wet end starch additives available for use. Modifications to starches generally fall under one of the following categories: 1) Physical modifications, 2) Fractionation into amylose and amylopectin components, 3) Thermomechanical conversion, 4) Acid hydrolysis, 5) Chemical modifications, 6) Oxidation, 7) Derivatization and 8) Enzyme conversion.

Starch derivatives are the most common type of dry strength additive used in the paper industry. The 1990 edition of the TAPPI publication “Commercially Available Chemical Agents for Paper and Paperboard Manufacture” lists 27 different starch dry strength products. Starch chemistry primarily centers on reactions with the hydroxyl groups and the glucosidic (C—O—C) linkages. Hydroxyl groups being subject to standard substitution reactions and the glucosidic linkages being subject to cleavage. In theory the primary alcohol at the C-6 position should be more reactive than the secondary alcohols at the C-2 and C-3 positions. Also, it has been found that the tuber starches are more reactive than the cereal starches.

A large variety of starch esters and ethers have been described. Few have been actively marketed due to non-specific properties resulting from the substitution groups. Esters will generally be prepared via reaction of the acid chloride or anhydride with the starch. Hydrophobic type structures can be introduced with this functionalization and such structures have found applications in the paper industry as adhesives, and grease resistant paper size coatings. (Starch Conversion Technology, 1985) Cationic starches are recognized as the choice for wet end additives due to their substantivity with cellulose fibers. The cationization of starches is accomplished by reaction with various tertiary and quaternary amine reagents. In general, a reactive chloride or epoxy group on one end of the reagent reacts with a starch hydroxyl group. The cationic portion of the amine then ionizes in the presence of water to form the positively charged derivative which is substantive to fiber.

Other ionic charged starches are produced by reaction of starch with amino, imino, ammonium, sulfonium, or phosphonium groups, all of which carry an ionic charge. The key factor in their usefulness is their affinity for negatively charged substrates such as cellulose. These cationic starches have found widespread use in the paper industry as wet end additives, surface sizing agents and coating binders. Cationic starches improve sheet strength by promoting ionic bonding and additional hydrogen bonding within the cellulose fibers. Some common reagents used to prepare cationic starches include: 2-diethylaminoethyl chloride (DEC); 2-dimethylaminoethyl chloride; 2-diisopropylaminoethyl chloride; 2-diethylaminoethyl bromide; 2-dimethylaminoisopropyl chloride; N-alkyl-N-(2-haloethyl)-aminomethylphosphonic acids; and 2,3-epoxypropyltrimethylammonium chloride.

Epichlorohydrin reacts with tertiary amines or their salts in water or nonaqueous solvents to form the quaternary ammonium reagents. Trimethylamine, dimethylbenzyl amine, triethylamine, N-ethyl and N-methyl morpholine, dimethylcyclohexylamine, and dimethyldodecylamine (Paschall, E. F., U.S. Pat. No. 2,876,217, 1959 and U.S. Pat. No. 995,513, 1961) have been used.

Cyanamide and dialkyl cyanamides can be used to attach imino carbamate groups on starches. These groups show cationic activity upon treatment with acids. The acidified products are stable to hydrolysis. Cationic cyanamide starches show useful properties as textile sizes and dry strength additives in paper. (Chamberlain, R. J., U.S. Pat. No. 3,438,970, 1969)

Aminoethylated starches are produced by treatment of ethyleneimine with starch in organic solvents or dry. Acidified products are useful as wet end paper additives (Hamerstrand, et al, “An evaluation of cationic aminoethyl cereal flours as wet end paper additives” Tappi, 58, 112, 1975). Starches react with isatoic anhydride and its derivatives to form anthranilate esters with primary or secondary amino groups (U.S. Pat. Nos., 3,449,886; 3,511,830; 3,513,156; 3,620,913). Products with primary amino anthranilate groups can be derivatized and used to improve wet rub resistance in paper coatings.

Cationic starches containing anionic xanthate groups provided both wet strength and dry strength to paper when used as wet end additives in unbleached kraft pulp systems. (Powers, et al, U.S. Pat. No. 3,649,624, 1972). In this system it is believed that the permanent wet strength results from covalent bonding from the xanthate side chain reactions. (Cheng, W. C., et al, Die Starke, 30, 280, 1978) Cationic dialdehyde starches are useful wet end additives for providing temporary wet strength to paper. They are produced by periodic acid oxidation of tertiary amino or quaternary ammonium starches, by treating dialdehyde starch with hydrazine or hydrazide compounds containing tertiary amino or quaternary ammonium groups, and several other reactions.

Graft copolymers of starch are widely known. Some graft copolymers made with starches include: vinyl alcohol; vinyl acetate; methyl methacrylate; acrylonitrile; styrene; acrylamide; acrylic acid; methacrylic acid; and cationic monomers with amino substituents including:2-hydroxy-3-methacrylopropyltrimethylammonium chloride (HMAC);N,N-dimethylaminoethyl methacrylate, nitric acid salt (DMAEMA*HNO3); N-t-butylaminoethyl methacrylate, nitric acid salt (TBAEMA*HNO3); and N,N,N-trimethylaminoethyl methacrylate methyl sulfate (TMAEMA*MS).

Polyacrylonitrile (PAN)/starch graft copolymers are well known in the art. Treatment of the PAN/starch graft copolymers with NaOH or KOH converts the nitrile substituents to a mixture of carboxamide and alkali metal carboxylate. Such hydrolyzed starch-g-PAN polymers (HSPAN) are used as thickening agents and as water absorbents. Important applications for HSPAN include use in disposable soft goods designed to absorb bodily fluids. (Lindsay, W. F., Absorbent Starch Based Copolymers—Their Characteristics and Applications, Formed Fabrics Industry, 8(5), 20, 1977).

Copolymers with water soluble grafts are also well known. Many of the water soluble graft copolymers are used for flocculation and flotation of suspended solids in the paper, mining, oil drilling and other industries. (Burr, R. C., et al, “Starch Graft Copolymers for Water Treatment”, Die Starke, 27, 155, 1975. Graft copolymers from the cationic amine containing monomers are effective retention aids in the manufacture of filled papers. Starch-g-poly(acrylamide-co-TMAEMA*MS) was found to improve drainage rates while increasing dry tensile strength of unfilled paper handsheets. (Heath, H. D., et al, “Flocculating agent-starch blends for interfiber bonding and filler retention, comparative performance with cationic starches”, TAPPI, 57(11), 109, 1974.) Thermoplastic-g-starch materials are also known, primarily with acrylate esters, methacrylate esters and styrene. Primary interest for these materials is in preparation of biodegradable plastics. No use of these materials as a paper additive has been found.

Other miscellaneous graft copolymers are known. Saponified starch-g-poly(vinyl acetate) has been patented as a sizing agent for cotton, rayon and polyester yarns. (Prokofeva, et al, Russian patent 451731, 1975). Graft copolymers have been saponified to convert starch-g-poly(vinyl acetate) copolymers into starch-g-poly(vinyl acetate) copolymers. As with the thermoplastic-g-starch copolymers most of these materials have been evaluated as polymeric materials in their own right and not as additives for paper.

Carboxymethyl cellulose, methyl cellulose, alginate, and animal glues are superior film formers. These materials are typically applied via surface application and not added in the wet end of the process to improve dry strength. The products are relatively expensive and although they can be used alone they are typically employed in conjunction with starches or other materials.

Gums

Gums and mucilages have been use in papermaking dates back to ancient China. These mucilages were obtained from various plant roots and stems and were used primarily as deflocculating and suspending agents for the long fibered pulps. As papermaking evolved other advantages of using these materials became obvious including the ability of these materials to hold the wet fiber mat together during the drying process. As papermaking evolved to using shorter and shorter fibers these gums found increased use as a means of obtaining paper strength. Since World War II the use of gums in papermaking has increased substantially.

Water soluble, polysaccharide gums are highly hydrophilic polymers having chemical structures similar to cellulose. The main chain consists of B-1,4 linked mannose sugar units with occurrence of a-1,6 linked galactose side chains. Their similarity to cellulose means they are capable of extensive hydrogen bonding with fiber surfaces. Further enhancement of dry strength occurs due to the linear nature of the molecules. They are vegetable gums and include as examples 1) locust bean gum, 2) guar gum, 3) tamarind gum, and 4) karaya, okra and others. Locust bean gum and guar gum are the most commonly used. They have been used in the paper industry since just prior to WWII. Since the natural materials are non-ionic they are not retained on fibers to any great extent. All successful commercial products have cationic groups attached to the main chain which increases the retention of the gums on the fiber surfaces. Typical addition rates for these materials are on the order of 0.1-0.35%.

The dry strength improvement of paper furnishes through use of polysaccharide gums is derived from the linear nature of the polymer and through hydrogen bonding of the hydroxyl hydrogen of the polymer with similar functional groups on the surface of the cellulosic fibers.

The most effective gums are quaternary ammonium chloride derivatives containing a cationic charge. The cationic functionality will help the gum retain better to the fibers as well as reducing the usually higher negative zeta potential of the paper furnish, especially when fillers and fines are present in the white water. This change in zeta potential leads to a more thorough agglomeration of the fines in the system by forming more cohesive flocs. These in turn are trapped by longer fibers filling the voids among the larger fibers with additional material that helps in the inter fiber bonding of the wet web, which in turn leads to dry strength improvement.

Although a variety of guar gum derivatives have been prepared, there are only three dervivatizations which have achieved commercial significance. These are 1) Quaternization, 2) Carboxymethylation and 3) Hydroxypropylation. As shown below the structure of guar gum and derivatives.

Chitosan

Chitosan is a high molecular weight linear carbohydrate composed of β-1,4-linked 2-amino-2-deoxy-D-glucose units. It is prepared from the hydrolysis of the N-acetyl derivative called chitin. Chitin is isolated in commercial quantities from the shells of crustaceans. Chitin is insoluble in most common solvents, however, chitosan is soluble in acidified water due to the presence of basic amino groups. Depending on the source and degree of deacetylation chitosans can vary in molecular weight and in free amine content. In sufficiently acidic environments the amino groups become protonated and chitosan behaves as a cationic polyelectrolyte. Chitosan has been used as an effective dry strength additive for paper.

The structure of chitosan is shown below.

Sugars

Also included in the saccharides are the simple sugars. These include the hexoses shown below. These compounds actually exist in the cyclic acetal form as shown below for glucose. Derivatives of these sugars are included within this definition. Such derivatives include but are not limited to things such as gluconic acid, mucic acid, mannitol, sorbitol, etc. The derivatives generally do not exist in cyclic form.

Aliphatic Hydrocarbon Moieties

Aliphatic hydrocarbons encompasses a broad group of organic compounds, including in general alkanes, alkenes, alkynes and cyclic aliphatic classifications. For purposes of this patent application, the aliphatic hydrocarbons can be linear or branched, saturated or unsaturated, substituted or non-substituted chain with a length of 8 or more carbon atoms.

Modified Polysaccharides Containing Aliphatic Hydrocarbons

Two primary methods are envisioned for incorporating aliphatic hydrocarbon moieties into the polysaccharide based materials. In the first scheme the hydrocarbon moieties are added via reaction between a functional group on the starch and a second functional group attached to the reagent containing the aliphatic hydrocarbon moiety. The polysaccharides may be derivatized or non-derivatized, cationic or non-cationic. The general reaction scheme is defined as follows:

Polysac—Z1+Z2—R1→Polysac—Z3R1

where:

Z1=functional group attached to the polysaccharide molecule and may be present either from the natural state or from a derivatization process. Examples of Z1 functional groups include but is not limited to —OH, —NH2, —COOH, —CH2X (X=halogen), —CN, —CHO, —CS2.

Z2=Functional group attached to the R1 moiety whose purpose is to react with a Z1 functional group thereby attaching the R1 moiety covalently to the polysaccharide.

R1=any organofunctional group with the only limitation being that R1 must contain a moiety consisting of a saturated or unsaturated, substituted or unsubstituted, linear or branched C8 or higher aliphatic hydrocarbon.

Z3=Bridging ligand formed as the result of reaction of Z1 with Z2.

Such materials in general will have a macroscopic structure as shown in FIG. 1 where the aliphatic moieties are attached in a pendant fashion to the polysaccharide. Where decreased water solubility becomes an issue a second moiety, containing a hydrophilic portion may be attached to the polysaccharide. Examples of such materials would include ethylene glycol and its oligomers and polymers.

In theory the Z2—R1 reactant could be difunctional of the form Z2—R2—Z2, however, in the case of most high molecular weight polysaccharides this crosslinking would be expected to lead to water insoluble products, suitable perhaps for coatings but not useful for wet end applications.

Synthesis of modified polysaccharides similar to those in FIG. 1 could be prepared via a number of methods. Attachment of the aliphatic hydrocarbon moiety could be achieved via the following paths:

1) Modified cationic polysaccharides prepared via reaction with one of the following or similar reagents:

 where R1, R2, R3 are any alkyl groups, chosen such that at least one of R1, R2, or R3 is linear or branched, saturated or unsaturated, substituted or unsubstituted C8 or higher aliphatic hydrocarbon.

More specifically defined examples of this approach are as follows:

i.) Were R3 is an alkyl group of the form —(CH2)n— where n=1 to 4, and R1 and/or R2 is a long chain alkyl group, linear or branched of 8 or more carbons

ii.) Where R3 a polyethylene glycol residue {—(CH2CH2O)n—} and R1 and R2 are alkyl groups.

iii.) Where R3 is a polytetraflouroethylene residue {—(CF2CF2)n—} and R1 and R2 are alkyl groups.

Note that in case (ii.) a hydrophilic entity in the form of the polyethylene glycol radical has been introduced into the polysaccharide product as well.

2) Dialdehyde polysaccharides, particularly dialdehyde starches, cationic or non-cationic, modified with fatty acid groups via reaction of the aldehyde groups with alcohols, amines, sulfinic acids, sulfyhydryl compounds and the like containing a linear or branched, saturated or unsaturated, substituted or non-substituted C8 or higher aliphatic hydrocarbon moiety.

Incorporation of a hydrophilic moiety may be accomplished through co-addition of a monosubstituted polyoxyalkane derivative of the form

HO—[(CHR4)nO]m—R5

where

R4=H, CH3, n=1 to 4,

R5=CH3, C2H5, etc.

m≧1

Alternatively, ethoxylated fatty acid derivatives of the following form can be used to directly incorporate both functionalities onto the polysaccharide backbone as shown below.

HO—(CH2CH2O)nR6

where

R6 is an organofunctional radical containing a linear or branched, saturated or unsaturated, substituted or non-substituted C8 or higher aliphatic hydrocarbon moiety.

3) Direct reaction of a functionalized linear or branched, saturated or unsaturated, substituted or non-substituted C8 or higher aliphatic hydrocarbon moiety with the hydroxyl or amine groups on the polysaccharide. An example of such a reaction is shown below for chitosan with 2-Octadecen-1-ylsuccinic anhydride.

4) Graft polymerization of hydrophobic and or hydrophilic units onto the polysaccharide backbone. Modified vinyl monomers are capable of being grafted onto polysaccharide backbones as has been demonstrated for various starches. Use of modified vinyl monomers such as:

 where:

R2=H, C1-4 alkyl.

R4=Z2—R6—Y radical where:

Z2=Ar, CH2, COO—, CONH—, —O—, —S—, —OSO2O—, —CONHCO—, —CONHCHOHCHOO—, any radical capable of bridging the R6 group to the vinyl backbone portion of the molecule.

R6=any aliphatic, linear or branched, saturated or unsaturated, substituted or non-substituted hydrocarbon.

Y=H, —N+R7R8R9, —NR7R8, where R7, R8, R9 are same or different and are H or C1-30 aliphatic hydrocarbons.

At least one of R6, R7, R8, R9 must be a C8 or higher, linear or branched, substituted or non-substituted, aliphatic hydrocarbon.

If desired hydrophilicity can be introduced through co-polymerization of modified vinyl polymers containing hydrophilic pendant groups such as:

where:

R2=H, C1-4 alkyl.

R5=any hydrophilic group including —COOH, —CONH2, —COO, —(CH2CH2O)nOH.

A specific example is shown below:

In the first method for incorporating aliphatic hydrocarbon moieties into the polysaccharide and monosaccharide based materials, the hydrocarbon moieties are added via reaction between a functional group on the starch and a second functional group attached to the reagent containing the aliphatic hydrocarbon moiety.

In the second method, however, two functional groups are attached to hydrocarbon containing reagent. The polysaccharides may be derivatized or non-derivatized, cationic or non-cationic. The general reaction scheme is defined as follows:

Polysac—Z1+Z2—R1—Z2→—Polysac—Z3R1—Polysac—

where:

Z1=functional group attached to the polysaccharide molecule and may be present either from the natural state or from a derivatization process. Examples of Z1 functional groups include but is not limited to —OH, —NH2,—COOH, —CH2X (X=halogen), —CN, —CHO, —CS2.

Z2=Functional group attached to the R1 moiety whose purpose is to react with a Z1 functional group thereby attaching the R1 moiety covalently to the polysaccharide.

Z3=Bridging radical formed as the result of reaction of Z1 with Z2.

R1=any organofunctional group with the only limitation being that R1 must contain a moiety consisting of a saturated or unsaturated, substituted or unsubstituted, linear or branched C8 or higher aliphatic hydrocarbon.

Such materials in general will have a macroscopic structure as shown in FIG. 2 where the aliphatic moieties are attached in series to the polysaccharide or monosaccharide molecules. When employed in cellulosic structures these materials can be thought of as providing “spot welds” to the web consisting of regions of strong hydrogen bonding connected to other regions of high hydrogen bonding through flexible non-bonding links. The combination of such properties could provide for a cellulosic product having a very unusual combination of strength and softness.

Where decreased water solubility becomes an issue a second moiety, containing a hydrophilic portion may be attached to the polysaccharide. Examples of such materials would include ethylene glycol and its oligomers and polymers.

In theory the polysaccharides could be of high molecular weight, however, the crosslinking would be expected to lead to water insoluble products, suitable perhaps for coatings but not useful for wet end applications. For wet end applications lower molecular weight polysaccharides including the oligomers as well as the monosaccharides and sugar derivatives are better candidates for this approach.

Synthesis of modified polysaccharides similar to those in FIG. 2 could be prepared via a number of methods. A few specific examples follow:

1) Polysaccharides crosslinked with α,ω-diacids or diacid halides of the formula:

 where:

Z=OH, halogen, other displaceable group.

Y=any residue chosen such that Y contains a C8 or higher, linear or branched, saturated or unsaturated, substituted or non-substituted aliphatic hydrocarbon.

For example, polysaccharides may be crosslinked with α,ω-diacids or diacid chlorides of the following formula:

where:

Z=OH, halogen, any other displaceable group.

n=8 or higher

Where additional hydrophilic character is desired a second reagent of the same type can be employed with the exception that Y=any hydrophilic residue. A specific example would be:

HOOCCH2(OCH2CH2)nOCH2COOH

where

n=2-1000.

The displaceable groups on the reactants can react with either primary —OH or —NH2 groups on the saccharide to form the corresponding ester or amide.

Figure below illustrates a specific synthetic approach to making such polysaccharides:

Many sugar derivatives contain α,ω-difunctionality and can lend themselves well to copolymer formation. For example, the following is illustrative of an aliphatic hydrocarbon sugar derivative combination. In this particular example strength is developed through hydrogen bonding via the polyhydroxy component while the aliphatic hydrocarbon portion provides a unique softness component.

where:

x=y≧1

n≧1

It will be appreciated that the foregoing examples, given for purposes of illustration, shall not be construed as limiting the scope of this invention, which is defined by the following claims and all equivalents thereto.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2661349Feb 18, 1949Dec 1, 1953Nat Starch Products IncPolysaccharide derivatives of substituted dicarboxylic acids
US2876217Dec 31, 1956Mar 3, 1959Corn Products CoStarch ethers containing nitrogen and process for making the same
US2926116Sep 5, 1957Feb 23, 1960Hercules Powder Co LtdWet-strength paper and method of making same
US2926154Mar 3, 1959Feb 23, 1960Hercules Powder Co LtdCationic thermosetting polyamide-epichlorohydrin resins and process of making same
US2995513Dec 31, 1957Aug 8, 1961Corn Products CoFlocculation by starch ethers
US3128311Dec 11, 1961Apr 7, 1964Jefferson Chem Co IncPreparation of primary amines
US3152998Jun 8, 1960Oct 13, 1964Jefferson Chem Co IncNickel-copper-chromia catalyst and the preparation thereof
US3155728Oct 11, 1960Nov 3, 1964Jefferson Chem Co IncMethod for the preparation of polyglycol primary amine
US3236792 *Dec 12, 1963Feb 22, 1966Miles LabWater-dispersible form of dialdehyde polysaccharides and process therefor
US3236895Dec 12, 1960Feb 22, 1966Dow Chemical CoPolyoxyalkylenepolyamines
US3240721Jun 30, 1960Mar 15, 1966Rohm & HaasAlkylene oxide adducts of polyalkylene- polyamine-epihalohydrin condensation products
US3250664Oct 24, 1963May 10, 1966Scott Paper CoProcess of preparing wet strength paper containing ph independent nylon-type resins
US3347926Apr 15, 1964Oct 17, 1967Atlas Chem IndAmmonolysis process for producing aliphatic amines
US3434984Apr 25, 1966Mar 25, 1969Owens Illinois IncThermosetting cationic resin and method of making same
US3436359Oct 14, 1965Apr 1, 1969Minnesota Mining & MfgPolyether polyprimary polyamines and elastomeric products thereof
US3438970Nov 13, 1964Apr 15, 1969American Cyanamid CoStorage-stable cyanamide-starch and method for the manufacture thereof
US3449886Jun 7, 1967Jun 17, 1969Stanco Packaging Systems CorpMethod and means for skin packaging articles on a porous substrate
US3511830Aug 27, 1968May 12, 1970Standard Brands IncStarch product
US3513156Aug 27, 1968May 19, 1970Speakman Edwin LEsters of starch and anthranilic acid and derivatives thereof
US3609126Mar 6, 1968Sep 28, 1971Toho Chem Ind Co LtdProcess for producing water-soluble thermosetting polymer
US3620913Mar 3, 1970Nov 16, 1971Cpc International IncA process of making paper and paper made therefrom using starch anthranilate
US3649624Dec 12, 1969Mar 14, 1972Staley Mfg Co A ECarboxyl starch amine ethers
US3654370Aug 28, 1970Apr 4, 1972Jefferson Chem Co IncProcess for preparing polyoxyalkylene polyamines
US3770472 *May 9, 1972Nov 6, 1973Nat Starch Chem CorpProcess for preparing modified starch dispersions
US3793279Nov 8, 1972Feb 19, 1974Diamond Shamrock CorpMono primary polyamine and organic dihalide modified,epoxidized polyamide for paper wet strength resin
US3893885Nov 23, 1973Jul 8, 1975Bayer AgAuxiliaries for the manufacture of paper
US3940519May 15, 1974Feb 24, 1976Kemanord AbProcess for sizing cellulose fibres
US4014933Aug 27, 1973Mar 29, 1977Basf AktiengesellschaftProduction of amines from alcohols
US4066495Jun 26, 1974Jan 3, 1978Anheuser-Busch, IncorporatedMethod of making paper containing cationic starch and an anionic retention aid
US4153581Sep 1, 1977May 8, 1979The Dow Chemical CompanyAmmonolysis using catalyst containing cobalt, copper and iron, zinc and/or zirconium
US4267059Oct 15, 1979May 12, 1981Wolff Walsrode AktiengesellschaftAuxiliary for improving retention, dewatering and working up, particularly in the manufacture of paper
US4278573 *Apr 7, 1980Jul 14, 1981National Starch And Chemical CorporationPreparation of cationic starch graft copolymers from starch, N,N-methylenebisacrylamide, and polyamines
US4447498Dec 1, 1982May 8, 1984Th.Goldschmidt AgUse of organopolysiloxanes in the manufacture of paper-coated plaster boards
US4450045Sep 10, 1982May 22, 1984Basf AktiengesellschaftPreparation of water-soluble, nitrogen-containing condensates and their use in papermaking
US4501640Oct 18, 1983Feb 26, 1985Kimberly-Clark CorporationCreping adhesives containing polyvinyl alcohol and cationic polyamide resins
US4521490Aug 11, 1983Jun 4, 1985Minnesota Mining And Manufacturing Co.Storage-stable adhesive of a colloidal dispersion of epoxy, an in situ-polymerized elastomer and a poly/oxyhydrocarbolene diamine curing agent
US4741804 *Apr 3, 1987May 3, 1988National Starch And Chemical CorporationPolysaccharide derivatives containing aldehyde groups, their preparation from the corresponding acetals and use as paper additives
US4764418Feb 28, 1986Aug 16, 1988Kimberly-Clark CorporationTissue paper with carboxylic acid; softness, multilayer
US4766245Mar 1, 1985Aug 23, 1988Texaco Inc.Process for the preparation of polyoxyalkylene polyamines
US4788243Apr 8, 1987Nov 29, 1988Kimberly-Clark CorporationCreping adhesives containing polyvinyl alcohol and thermoplastic polyamide resins derived from poly(oxyethylene) diamine
US4801699 *Mar 9, 1987Jan 31, 1989National Starch And Chemical CorporationPolysaccharide esters containing acetal and aldehyde groups
US4824689Nov 2, 1987Apr 25, 1989Kimberly-Clark CorporationMethod for producing virucidal tissue products containing water-soluble humectants
US4866151 *Oct 26, 1987Sep 12, 1989National Starch And Chemical CorporationPolysaccharide graft polymers containing acetal groups and their conversion to aldehyde groups
US4959125Dec 5, 1988Sep 25, 1990The Procter & Gamble CompanySoft tissue paper containing noncationic surfactant
US4973680Mar 3, 1989Nov 27, 1990National Starch And Chemical Investment Holding CorporationOrganosiloxane-containing polysaccharides
US4983748 *Dec 28, 1988Jan 8, 1991National Starch And Chemical Investment Holding CorporationAcetals useful for the preparation of polysaccharide derivatives
US5174927Sep 6, 1991Dec 29, 1992The Procter & Gamble CompanyDetergent and builders
US5354425 *Dec 13, 1993Oct 11, 1994The Procter & Gamble CompanyTissue paper treated with polyhydroxy fatty acid amide softener systems that are biodegradable
US5518585Feb 23, 1995May 21, 1996Hoechst AktiengesellschaftNeutral sizing agent for base paper stuff with the use of cationic plastics dispersions
US5525345 *Mar 6, 1995Jun 11, 1996The Proctor & Gamble CompanyPetroleum based emollient or fatty ester emollient, polyhydroxy fatty ester or amide immobilizing agent
US5552020Jul 21, 1995Sep 3, 1996Kimberly-Clark CorporationTissue products containing softeners and silicone glycol
US5575891Jan 31, 1995Nov 19, 1996The Procter & Gamble CompanySoft tissue paper containing an oil and a polyhydroxy compound
US5578678Apr 19, 1994Nov 26, 1996Basf AktiengesellschaftGraft polymers of natural substances containing saccharide structures or derivatives thereof and ethylenically unsaturated compounds and their use
US5591306Mar 18, 1996Jan 7, 1997Kimberly-Clark CorporationMethod for making soft tissue using cationic silicones
US5612443 *Jun 2, 1995Mar 18, 1997National Starch And Chemical Investment Holding CorporationFormaldehyde-free crosslinking agents
US5624532Feb 15, 1995Apr 29, 1997The Procter & Gamble CompanyMethod for enhancing the bulk softness of tissue paper and product therefrom
US5626719 *Jun 7, 1995May 6, 1997Hercules IncorporatedThermosetting resin, reactive and non-reactive size, waterproof beverage container
US5656746 *Mar 28, 1996Aug 12, 1997The Proctor & Gamble CompanyTemporary wet strength polymers from oxidized reaction product of polyhydroxy polymer and 1,2-disubstituted carboxylic alkene
US5716692 *Feb 28, 1996Feb 10, 1998The Procter & Gamble Co.Lotioned tissue paper
US5717087 *Aug 2, 1996Feb 10, 1998Wolff Walsrode AgFor molded parts, sheets, fibers, coatings, blends, laminates, matrices for delayed release of active materials, paper coatings
US5746887Apr 24, 1996May 5, 1998Kimberly-Clark Worldwide, Inc.Impression knuckles create projections in throughdried sheet imparting cross-machine direction stretch
US5770711 *Sep 30, 1996Jun 23, 1998Kimberly-Clark Worldwide, Inc.Derivatized with 2,3-epoxysuccinic acid, 1,2-epoxypropane-1,2,3-tricarboxylic acid, and or 2-(epoxyethyl)succinic acid; crosslinking
US5772845Oct 17, 1996Jun 30, 1998Kimberly-Clark Worldwide, Inc.Soft tissue
US5785813Feb 24, 1997Jul 28, 1998Kimberly-Clark Worldwide Inc.Method of treating a papermaking furnish for making soft tissue
US5856299 *Mar 13, 1995Jan 5, 1999Fidia Advanced Biopolymers S.R.L.Highly reactive esters of carboxy polysaccharides and carboxy polysaccharides derived therefrom
US5958187 *Jul 11, 1997Sep 28, 1999Fort James CorporationBiodegradable tissue paper
US6059928 *Sep 18, 1995May 9, 2000Fort James CorporationPrewettable high softness paper product having temporary wet strength
US6090242Apr 6, 1999Jul 18, 2000Minerals Technologies Inc.Method of improvement strength of papers
US6126784 *May 5, 1999Oct 3, 2000The Procter & Gamble CompanyDepositing the chemical additive including a softener only to the first side of the fibrous web, partially transferring the chemical additive from the first side to the second side of the fibrous web, winding the web into a roll
US6153053Apr 15, 1998Nov 28, 2000Fort James CorporationSoft, bulky single-ply absorbent paper having a serpentine configuration and methods for its manufacture
US6190678 *Sep 4, 1998Feb 20, 2001The Procter & Gamble CompanyComprises water insoluble substrate, lathering surfactant, and a conditioning component; lathering at low surfactant levels, cleansing and exfoliation, and delivery and deposition of conditioning ingredients result, this inventi
US6193843Jun 1, 1994Feb 27, 2001National Starch And Chemical Investment Holding CorporationCationic polysaccharides and reagents for their preparation
US6204254Sep 12, 1997Mar 20, 2001Baxter International, Inc.Biocompatible surfaces and a method for their preparation
US6207012May 24, 2000Mar 27, 2001Fort James CorporationHydrophilic, humectant, soft, pliable, absorbent paper having wet strength agents
US6207013May 24, 2000Mar 27, 2001Fort James CorporationForming nascent web; air drying
US6235155Jan 20, 2000May 22, 2001Kimberly-Clark Worldwide, Inc.Modified condensation polymers having azetidinium groups and containing polysiloxane moieties
US6398911Jan 21, 2000Jun 4, 2002Kimberly-Clark Worldwide, Inc.Used as coatings on paper sheets; strengthening agents, binders, emulsifiers and adhesives
US20020074098Oct 31, 2001Jun 20, 2002Shannon Thomas GerardModified condensation polymers containing azetidinium groups in conjunction with amphiphilic hydrocarbon moieties
USRE30193 *Feb 11, 1976Jan 15, 1980 Calcium borates and a halogen source
CA2296826A1Jan 24, 2000Jul 25, 2000Kimberly-Clark Worldwide, Inc.Modified condensation polymers containing azetidinium groups in conjunction with aliphatic hydrocarbon moieties suitable for papermaking
CA2296891A1Jan 24, 2000Jul 25, 2000Kimberly-Clark Worldwide, Inc.Modified condensation polymers containing azetidinium groups in conjunction with amphiphilic hydrocarbon moieties
CA2296894A1Jan 24, 2000Jul 25, 2000Kimberly Clark CoModified condensation polymers having azetidinium groups and containing polysiloxane moieties
DE2247943A1Sep 29, 1972Apr 26, 1973Orion Yhtymae OyVerfahren zum vernetzen von agarose oder agar
EP0469891A1Jul 31, 1991Feb 5, 1992Hercules IncorporatedProcess for the production of improved polyaminopolyamide epichlorohydrin resins
EP0620315A1Apr 7, 1994Oct 19, 1994Cerestar Holding BvPaper sizing process and composition therefor
EP0761691A2May 10, 1996Mar 12, 1997National Starch and Chemical Investment Holding CorporationProcess for the preparation of hydrophobic starch derivatives
WO1999012977A1Sep 2, 1998Mar 18, 1999Hagberg PeggyModified starch
Non-Patent Citations
Reference
1Burr, R.C., et al., "Starch Graft Copolymers for Water Treatment," Die Starke, 27, Nr. 5, 1975, pp. 155-159.
2Cheng, W.C., et al., "O-Carboxymethylstarch Amine Polyampholytes as Papermaking Additives," Starch/Stärke, vol. 30, No. 8, Aug. 1978, pp. 280-282.
3Derwent World Patent Database abstract of SU 451,731: Description of Vladimir Synth Resi, "Cyanoethylated Starch Adhesive for Electroluminescent Lamps."
4Farewell, John, Editor, Commercially Available Chemical Agents for Paper and Paperboard Manufacture, Fourth Edition, Tappi Press, 1990, pp. 5-6.
5Hamerstrand, G.E., et al., "An Evaluation of Cationic Aminoethyl Cereal Flours as Wet-End Paper Additives," Tappi, vol. 58, No. 1, Jan. 1975, pp. 112-115.
6Heath, H.D., et al., "Flocculating Agent-Starch Blends for Interfiber Bonding and Filler Retention: Comparative Performance With Cationic Starches," Tappi, vol. 57, No. 11, Nov. 1974, pp. 109-111.
7Lindsay, William F., "Absorbent Starch Based Co-polymers-Their Characteristics and Applications," Formed Fabrics Industry, 8(5), 1977, pp. 20, 24, 26.
8Lindsay, William F., "Absorbent Starch Based Co-polymers—Their Characteristics and Applications," Formed Fabrics Industry, 8(5), 1977, pp. 20, 24, 26.
9Van Beynum, G.M.A., editor, Starch Conversion Technology, Marcel Dekker, Inc., New York, 1985, pp. 92-93.
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US20130299109 *Sep 30, 2011Nov 14, 2013Matti HietaniemiMethod for improving papermaking or board making process, use of a polysaccharide and paper
CN102443067BOct 28, 2011Mar 20, 2013东北林业大学Method for preparing carboxide modified nanometre cellulose
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Classifications
U.S. Classification162/177, 162/157.6, 162/184, 162/183, 162/186, 162/185, 162/175, 162/157.1
International ClassificationD21H17/24, C08B11/20, C08B15/06, C08B37/00, C08B31/00, C08B15/00
Cooperative ClassificationC08B15/005, C08B15/06, D21H17/24, C08B15/00, C08B11/20, C08B37/00, C08B31/003, C08B31/00
European ClassificationC08B31/00B, D21H17/24, C08B11/20, C08B31/00, C08B37/00, C08B15/00, C08B15/00B, C08B15/06
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